NORTH TEXAS (CBSDFW.COM) – A new study raises questions about how safe it is for teenagers to play high school football.

The research, presented for the first time on Monday at a medical conference in Chicago, shows high school players’ brains changed after a season of high school football, even when they never suffered a concussion.

“What we found were changes in the brain after a single season of football that were associated to cumulative head impact exposures,” said Dr. Christopher Whitlow, lead researcher on the Wake Forest Baptist Medical Center study.

His research also showed more microstructural brain changes in the players who hit harder and more frequently.

The cognitive effects of the brain changes, however; remain unclear.

“Football is a physical sport,” Arlington-Martin High School head football coach Bob Wagner said. “Anything we can do to help these kids be safer, I’m all for.”

Wagner said he hopes the study leads to more research, and not panic about the dangers of football.

Dr. Whitlow also believes more research is needed to try and determine whether the changes in the brain are permanent or transient.

“There’s risk in football,” said Wager. “But there are some unbelievable positive things that come along with it as well.”